Contains manuscripts for 47 mystery novels written by American detective fiction writer Aaron Marc Stein.

Consists of papers of American architect and poet Edward Steese, including diaries, manuscripts, and architectural drawings.

Consists of papers of the American literary critic and novelist Donald A. Stauffer (1902-1952, Princeton Class of 1923).

Consists of correspondence, photographs, newspapers, and ephemera belonging to missile researcher Warren Alfred Stark that document his time in the United States Army at the White Sands Proving Grounds in New Mexico during the Korean War and the early years of the Cold War. The majority of the collection consists of correspondence between Warren Stark and Jean Anne Baldwin Stark (1928-1999), his girlfriend and later wife, and other family members and close friends.

Princeton professor of astronomy (1947-1982), chairman of the Dept. of Astrophysical Sciences, and director of the Princeton University Observatory, Lyman Spitzer was also primarily responsible for founding the University's Plasma Physics Laboratory. His papers include design studies, technical plans and programs, various reports, correspondence, notes, and observations relating to his involvement in the development of the study of space astronomy at Princeton.

Consists of personal journals of Theodore Spencer, American poet and essayist, and distinguished Harvard University literature professor.

Davis Spencer (1924-2005), a member of the Class of 1945, rowed on Princeton's freshman and varsity crews, and coached the 150-pound crew team that won the Royal Henley Regatta in 1948. The papers document Princeton's varsity 150-pound crew team as competitors and victors of the 1948 Royal Henley Regatta.

Consists of papers relating to post-World War II Greek history and politics, 1940s-1970s, collected by Norma Spector in her role as the public relations liaison of the Federation of Greek Maritime Unions (FGMU) in New York City.

Walter E. Spahr (1891-1970) was a professor of economics at New York University who was a strong supporter of the gold standard. Spahr was a founding member and officer of the Economists' National Committee for Monetary Policy, which advocated for sound monetary policies for the United States. Spahr's papers document his scholarship and include his writings and related correspondence.

Consists of a photograph album, loose photographs, and clippings belonging to Robert J. Sommers (1881-1972), primarily documenting his work as a highway engineer in Alaska in the late 1920s, as well as some materials related to his personal life and career as a civil engineer and businessman involved in construction. Of note is a photograph album documenting a tour of Alaska made in 1928 by Sommers with Governor George A. Parks and Major Malcolm Elliott.

Consists of selected material by and about Henry De Wolf Smyth, the American physicist and diplomat who figured prominently in the development of atomic energy, the Manhattan Project, and the production of the atomic bomb.

Consists of the papers of Princeton chemistry professor Charles Phelps Smyth.

Consists chiefly of correspondence of British musicologist William Charles Smith related to music and to George Frederic Handel.

Consists primarily of correspondence between childhood friends William B. Smith and Ernest Hemingway, the American author and Nobel Prize winner.